Bump bonding device and bump bonding method

ABSTRACT

To eliminate breakage of electronic parts or defective bonding, and enhance reliability of electronic parts, in regulation of electronic parts in bump bonding device. A bump bonding device comprising a stage  1  for mounting and heating an electronic part, and a position regulating device including a rotatable regulating plate  2  having a side for positioning the electronic part, a plate  4  having a side for positioning the electronic part in collaboration with the regulating plate, and a regulating spring  5  for applying a regulating force to the regulating plate in order to press the electronic part to the plate  4.

TECHNICAL FIELD

[0001] The present invention relates to a bump bonding device forforming bump electrodes on electrodes of semiconductor electronic parts,and its method.

BACKGROUND ART

[0002] Referring to FIG. 6 to FIG. 11, conventional bump bonding deviceand bump bonding method are described below.

[0003]FIG. 6 is a perspective view of a bump bonding device for forminga bump on an electronic part 3 by using a gold wire 13.

[0004] In the diagram, the electronic part 3 supplied from a tray 10 isfixed on a heated stage 1 by means of a suction collet 11. A capillary12 is held by an ultrasonic feed unit, and is provided with anultrasonic wave, and a gold bump is formed on the electrode of theelectronic part 3 by the capillary 12 in which the gold wire 13 ispassed. After forming bumps on specified positions thereof, theelectronic part 3 is stored in a tray 10 a by means of the suctioncollet 11.

[0005]FIG. 7 is a process diagram showing the bump forming process.

[0006] First, at step (a), the gold wire 13 is passed in the capillary12, a spark is ignited on the tip of the gold wire 13, and a ball isformed on the tip. At next step (b), the capillary 12 is lowered topress on an electrode 14 of the electronic part 3. At this time, anultrasonic wave is applied to bond the electrode 14 and gold wire 13(1st bonding). At step (c), consequently, the capillary 12 is lifted,and is lowered again while controlling the loop, and, at step (d), thecapillary 12 presses on the gold ball of first bonding, and cuts off thegold wire 13 (2nd bonding).

[0007] A regulating section of electronic parts is described in detailbelow.

[0008]FIG. 8 is a plan view of electronic parts regulating section.

[0009] As shown in FIG. 8, the regulating section of the bump bondingdevice is composed of a stage 1 having a suction hole, a regulating pawl2 movable in the XY direction, and a regulating spring 5 for applying aregulating force in the Y direction of the regulating pawl 2, in whichthe electronic part 3 moves on the suction hole of the stage 1 by meansof the regulating pawl 2, and is regulated in position on the stage 1 byvacuum suction. However, the suction force is insufficient for a tinyelectronic part, a regulating section as shown in FIG. 9 is used.

[0010] As shown in FIG. 9, the regulating section is composed a stage 1,a plate 4 fixed at an end of the stage 1, a regulating pawl 2 movable inthe XY direction, and a regulating spring 5 for applying a regulatingforce in the Y direction of the regulating pawl 2.

[0011] In this regulating section, it is hard to set the regulating pawlparallel to the plate 4, and therefore when regulating the position ofthe electronic part 3, if a regulating force is applied to theelectronic part 3 by the regulating pawl 2, a corner 3 a of theelectronic part may collide against the plate 4, and the electronic partmay be broken.

[0012]FIG. 10 is a flowchart showing operation by the conventionalelectronic parts regulating device.

[0013] The electronic part is put on the stage 1 of the bump bondingdevice, the suction device is turned on, the electronic part ispositioned, and, in this state, the electronic part 3 is bonded. In thecase of a tiny electronic part, however, the suction hole is not suitedto the dimension of the electronic part, or the suction hole located onthe regulating track of the electronic part cannot be blocked accordingto the dimension of the electronic part, and suction errors often tookplace.

[0014] Generally, a tiny electronic part is fragile, and therefore whenhandling a tiny electronic part, it is required to decrease the impactforce when regulating the position to prevent breakage of electronicpart. It is hence an object of the invention to present an electronicpart of high reliability, free from breakage when positioning theelectronic part. Besides, if suction error occurs, the electronic partis likely to be cooled and defective bonding is caused, and, therefore,by preventing suction error, it is also an object of the invention topresent an electronic part of high reliability with a lower rate ofdefective bonding.

SUMMARY OF THE INVENTION

[0015] The bump bonding device of the invention comprises a stage formounting and heating an electronic part, and a position regulatingdevice of electronic part including a rotatable regulating plate havinga side for positioning the electronic part, a plate having a side forpositioning the electronic part in collaboration with the regulatingplate, and a regulating spring for applying a regulating force to theregulating plate in order to press the electronic part to the plate, andtherefore the electronic part is regulated as being bonded between theregulating plate and the plate surface, and breakage is prevented, sothat the reliability of electronic parts can be enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a plan view showing a regulated state of an electronicpart in an embodiment of the invention.

[0017]FIG. 2 is a plan view showing a regulated state of an electronicpart in an embodiment of the invention.

[0018]FIG. 3 is a plan view showing a regulated state of an electronicpart in an embodiment of the invention.

[0019]FIG. 4 is a plan view showing configuration of suction holes andmoving track of electronic parts in an embodiment of the invention.

[0020]FIG. 5 is a flowchart showing regulating action of electronic partin an embodiment of the invention.

[0021]FIG. 6 is a perspective view of a conventional bump bondingdevice.

[0022]FIG. 7 is a bump bonding process diagram showing a conventionalbump shape.

[0023]FIG. 8 is a plan view showing a regulated state of a conventionalelectronic part.

[0024]FIG. 9 is a plan view showing a regulated state of a conventionalelectronic part.

[0025]FIG. 10 is a flowchart showing action by a conventional regulatingdevice of electronic parts.

BEST MODE OF CARRYING OUT THE INVENTION

[0026] The invention as set forth in claim 1 comprises a stage formounting and heating an electronic part, and a position regulatingdevice including a rotatable regulating plate having a side forpositioning the electronic part, a plate having a side for positioningthe electronic part in collaboration with the regulating plate, and aregulating spring for applying a regulating force to the regulatingplate in order to press the electronic part to the plate, and thereforethe electronic part is regulated in position as being bonded between thesurfaces of the regulating plate and the plate, and breakage of theelectronic part is prevented, so that the reliability of electronic partcan be enhanced.

[0027] In the invention as set forth in claim 2, the rotatableregulating plate is provided with a balance spring at right angle to theregulating spring in order to prevent excessive rotation in the rotatingdirection, and the same action as in claim 1 is obtained.

[0028] In the invention as set forth in claim 3, a regulating spring isprovided at one side of the balance spring, and the regulating force isapplied also to the balance spring, and the same action as in claim 1 isobtained.

[0029] The invention as set forth in claim 4 relates to a bump bondingmethod in the bump bonding device disposed on the moving track ofelectronic parts when regulating the electronic parts, and havingsuction holes for sucking electronic parts by vacuum, which comprises astep of putting electronic parts on a stage, a step of turning onsuction of electronic parts by suction holes in the stage, a step ofmoving electronic parts along the suction holes arranged on the movingtrack of the electronic parts, and pressing the electronic parts to theplate by a regulating plate to position, and a step of turning off thesuction of electronic parts, and therefore cooling of electronic partsdue to suction error of electronic parts is prevented and defectivebonding is avoided, so that the reliability of electronic parts can beenhanced.

[0030] Embodiments of the invention are described below while referringto FIG. 1 to FIG. 5.

EMBODIMENT 1

[0031]FIG. 1 is a plan view showing a regulated state of an electronicpart in an embodiment of the invention, in which an electronic plate 3is supported by a plate 4 at one side, and by sides of a regulatingplate 2 at other two sides. The regulating plate 2 is provided with aregulating force in the spring direction by means of a regulating spring5, and is provided rotatably about a fulcrum 6. Therefore, whenregulating the position of the electronic part, since the electronicpart 3 is regulated in position by contacting with the surfaces of theregulating plate 2 and plate 4, concentrated load is not applied to theelectronic part 3, breakage of electronic part 3 is prevented, so thatthe reliability of the electronic part 3 can be enhanced.

EMBODIMENT 2

[0032]FIG. 2 is a plan view showing a regulated state of an electronicpart in other embodiment of the invention, the description of the sameconstitution as in FIG. 1 is omitted. In FIG. 2, what differs from FIG.1 is that a balance spring 7 is provided at right angle to theregulating spring 5. In this constitution, when the regulating plate 2rotates about the fulcrum 6, excessive rotation of the regulating plate2 is prevented by spring force by the balance spring 7, so that thesurface of the regulating plate 2 may be maintained at the same level asthe surface of the electronic part 3. Accordingly, same as in embodiment1, breakage of the electronic part 3 can be prevented.

[0033] As a specific example of this embodiment, the electronic part 3was made of a silicon IC chip measuring 1.4×1.3 (mm) and 0.3 (mm) inthickness, and the regulating spring 5 was adjusted in the regulatingpush-in extent so that the maximum load be 50 g, and a load of 200 g wasapplied to the actual electronic part 3. The maximum load of the balancespring 7 was 300 g each.

EMBODIMENT 3

[0034]FIG. 3 is a plan view showing a regulated state of an electronicpart in a different embodiment of the invention, the description of thesame constitution as in FIG. 2 is omitted. In FIG. 3, what differs fromFIG. 2 is that a regulating spring 5 b is provided in the same directionas the thrusting direction of the balance spring 7, and that notches areformed at four corners of the plate 4 so as to bonded with theelectronic part 3 at two sides. In this constitution, regulating forceis applied also in the thrusting direction of the balance spring 7, sothat the electronic part 3 may be fixed more stably.

EMBODIMENT 4

[0035]FIG. 4 is a plan view showing configuration of suction holes andmoving track of electronic parts in other different embodiment of theinvention, and FIG. 5 is a flowchart showing its action. In FIG. 4,reference numerals 8 a to 8 e are suction holes for sucking theelectronic part 3 by vacuum.

[0036] First, when the electronic part 3 is put on position 9 a of thestage 1, the electronic part 3 is sucked by the suction hole 8 a. Atthis time, if the electronic part 3 is not sucked by the suction hole 8a, the electronic part 3 rotates or sticks to the nozzle side ifattempted to mount. In FIG. 4, the regulating plate 2 is already incontact with the electronic part 3, but when the electronic part 3 isput on the stage 1, the electronic part 3 is no longer contacting withthe regulating plate, and they contact with each other only when theelectronic part 3 is sucked. Later, the electronic part 3 moves on thesuction holes 8 a to 8 e. At this time, all suction holes are sucking,the electronic part 3 moves neatly along the suction holes and is fixedat position 8 e (see embodiments 1 and 2). Then, the suction of thesuction holes 8 a to 8 e is cut off. In this constitution, occurrence ofsuction error can be prevented, and therefore the electronic part 3 isnot cooled, and defective bonding is prevented.

[0037] In this embodiment, five suction holes 8 are provided, but thenumber or configuration is not specifically defined, and various formsare possible. It is also applicable to the stage capable of bonding aplurality of electronic parts.

[0038] Industrial Applicability

[0039] Thus, according to the invention, since concentrated load is notapplied to a point of electronic part when regulating the electronicpart, breakage of electronic part can be prevented. Moreover, sincecooling of electronic part can be prevented, defective bonding can beavoided, so that the reliability of the electronic part can be enhanced.

1. A bump bonding device comprising a stage for mounting and heating anelectronic part, and a position regulating device including a rotatableregulating plate having a side for positioning the electronic part, aplate having a side for positioning the electronic part in collaborationwith said regulating plate, and a regulating spring for applying aregulating force to the regulating plate in order to press theelectronic part to the plate.
 2. A bump bonding device of claim 1,wherein the rotatable regulating plate includes with a balance springdisposed at right angle to the regulating spring in order to preventexcessive rotation in the rotating direction.
 3. A bump bonding deviceof claim 2, wherein said position regulating device a regulating springdisposed at one side of the balance spring, and the regulating force isapplied also to the balance spring by the regulating spring.
 4. A bumpbonding method in a bump bonding device which has suction holes forsucking electronic parts by vacuum and is disposed on a moving track ofelectronic parts when regulating the electronic parts, said methodcomprising the steps of; putting electronic parts on a stage, turning onsuction of electronic parts by suction holes in the stage, movingelectronic parts along the suction holes arranged on the moving track ofthe electronic parts, and pressing the electronic parts to the plate bya regulating plate to position, and turning off the suction ofelectronic parts.